Leader of the Northerners faction who served as Chief State Councillor during King Seonjo's reign

| Life | 1539 ~ 1609 |
| Era | 조선 |
| Clan | 한산 이씨 |
Yi San-hae came from the prestigious Hansan Yi clan, descended from the Goryeo scholar Yi Saek, and served as a court official under King Seonjo. He was honored as a third-class Merit Subject of State Restoration for his role in correcting Ming records about the Joseon founder, and was enfeoffed as Prince Aseong; his son Yi Gyeong-jeon and his son-in-law Yi Deok-hyeong tied him to other leading families of the era.
After serving as third and second state councillor, he rose to chief state councillor in 1590 and, following the Gichuk purge, became the leader of the Northerner faction dominating court politics. During the Japanese invasions he was exiled to Pyeonghae in Gangwon Province for advocating the king's flight, consoling himself with poetry and painting until his pardon in 1595. Renowned for his literary and artistic talent, he was regarded as the leading literary authority of Seonjo's reign and left behind the collected works Agyejip.
He was buried in Daesul-myeon, Yesan County, South Chungcheong Province, where a memorial stele composed by the Southerner chief minister Chae Je-gong was erected in 1819.
Bangsan-ri, Daesul-myeon, Yesan-gun, Chungcheongnam-do
His son Yi Gyeong-jeon rose to prominence as a civil official, and his son-in-law was Haneum Yi Deok-hyeong.